Complete lubricating system for engine-driven implement



Sept. 16, 1958 E. c. KIEKHAEFER 2,852,046

COMPLETE LUBRICATING SYSTEM FOR ENGINE-DRIVEN IMPLEMENT Filed April 18, 1955 2 Sheets-Sheet 1 ar p INVENTOR. ZEZMHP a. NEWMAN- m? BY H622.

'A T TORNEY Sept. 16, 1958 v E. c. KIEKHAEFER 2,852,046

COMPLETE LUBRICATING SYSTEM FOR ENGINE-DRIVEN IMPLEMENT Filed April 18, 1955 2 Sheets-Sheet 2 2a 7 E 30 27 29 i e :u I 4 3 25 23 2 INVENTOR. Ell. MM? 6. K/[KHAEFEP BY 6 4 9 AM? ATTORNEY COMPLETE LUBRICATING SYSTEM FOR ENGINE-DRIVEN IMPLEMENT This invention relates to a lubrication system for an implement such as a chain saw driven by an engine wherein the lubricant and fuel which is subject to crankcase induction and precompression is combined to provide the desired lubrication of the engine, gear transmission and chain or other external bearings. I

The invention provides the removal of excess liquid United States Patent fuel and-lubricant from the crank chamber and utilizes the intermittent pressure developed therein to direct a spray of fuel and lubricant against the rotating gears so that the deposited. lubricant flows toward the teeth and lubricates the same and the excess is applied to the saw chain.

The object of the invention is to provide the continuous lubrication of the gears and other parts without any given or accumulated supply of liquid lubricant.

The drawings furnished herewith illustrate the best mode of carrying out the invention as presently contemplated and setforth hereinafter.

In the drawings:

Figure 1 is a sectional view of an air-cooled two-cycle engine with the carburetor and fuel system associated therewith. The fuel tank is shown diagrammatically and connected to the carburetor for the supply of liquid fuel and lubricant to the carburetor;

Fig. 2 is a side elevation of a chain saw including the engine shown in Figure 1 and showing the sprocket and chain which according to the invention receives and utilizes the excess lubricant as provided and shown in Fig. 3; and

Fig. 3 is a sectional view showing in part the crank chamber of the engine shown in Figure 1 and showing the gear transmission of the chain saw unit driving the sprocket shown in Fig. 2.

The engine 1 shown in the drawings includes the crankcase 2 and the cylinder block 3 provided with the cylinder 4 carrying the piston 5 for reciprocation therein. The crankshaft 6 is carried by crankcase 2 with the crank throw 7 within the closed crank chamber 8 of the crankcase.

Engine 1 is of two-cycle operation employing crankcase precompression of the fuel and air mixture which is supplied to the engine by the carburetor 10 secured to crankcase 2. Carburetor 10 includes the mixing passage 11 for receiving air from the filtering device 12 and communicates with crank chamber 8 through the opening 13 in the plate 14 interposed between the carburetor and crankcase. The reed 15 is secured to the valve plate 14 to normally cover opening 13 and to allow a fresh charge of carbureted air and fuel to be drawn through opening 13 into chamber 8 as upon .upward movement of piston 5 compressing the fuel and air mixture in the combustion chamber 16 of cylinder 4. The ignition of the fuel charge in combustion chamber 16 by the spark plug 17 provides the downward power stroke of piston 5 which compresses the fuel and air mixture in crank-chamber 8. As piston 5 approaches the lower limit of its stroke, the piston uncovers the exhaust port 18 and similar adjacent 2,852,046 Patented Sept. 16, 1958 ports formed in cylinder block 3 to allow the exhaust of the burned gases from the combustion chamber 16 of cylinder 4.

Corresponding intake ports including the port 19 are similarly opened by piston 5 allowing the compressed fuel and air mixture within crank chamber 8 to be transferred through the passage 20 into cylinder 4 for the scavenging or displacement of the burned gases and the recharging of the cylinder.

One end of crank shaft 6 is formed with the gear teeth 21 as shown in Fig. 3 and is supported by the bearings 22 to drive the gear 23 carried by the bearing 24 in the chamber 25 of the member 26 forming part of crankcase 2.

The chain drive sprocket 27 of the unit is mounted on the shaft 28 which carries the manually controlled clutch element 29 in chamber 25 for selective engagement with gear 23 and to be driven by engine 1. Shaft 28 is pro vided with the 'bore 30 and the transversely drilled opening 31 extending through the shaft and the bore 30 provides the necessary communication between chamber 25 and the registering passages 32 and 33 formed in the shaft and sprocket 27 respectively.

Passage 33 in sprocket 27 opens radially outwardly of and between two of the teeth of the sprocket which drives the cutting chain 34 around the edge of the guide rail 35 fixed at one end to member 26 adjacent to the sprocket and in alignment therewith.

According to the invention, the entire lubrication of the engine, gear case and saw chain is provided by an oil lubricant added to the liquid fuel carried by the tank 36.

The/line 37 from tank 36 provides for delivery of liquid fuel and lubricant to the nozzle 38 extending into passage 11 of the carburetor. The liquid fuel vaporizes as it is carried in fine particles by the air passing nozzle 38 and into crankcase chamber 8, and is controlled so that the correct proportion of air and vapon'zed fuel reaches combustion chamber 16.

The lubricant is also carried into the crank chamber 8 in line particles to lubricate the wall of cylinder 4 and the several bearings therein associated with crankshaft 6 and piston 5.

According to the present invention, a controlled amount of air is periodically allowed discharge from chamber 8 into chamber 25 for the lubrication of gear 23 and gear teeth 21, and chamber 25 is vented between the teeth of sprocket 27 to provide the lubrication of sprocket 27 and chain 34.

The passage 39 in member 26 extending from a point near the bottom of chamber 8 opens into the adjacent chamber 25 and includes the larger bore 40 fitted with the ball check valve 41 which is seated by the spring 42 against a portion of member 26 forming the inner end of the bore. The plug 43 is press-fit in bore 40 to retain sprin 42 therein and is provided with a small drilled orifice 44 adjacent to and directed toward one side of gear 23,

Spring 42 is of a capacity which will normally maintain ball 41 seated to close passage 40 and to yield only to the maximum pressure periodically developed in chambet 8 as described so that a small amount of the fuel, lubricant and air mixture is allowed passage therethrough and is directed against gear 23 by the orifice 44. The amount of air and fuel necessary to maintain fully adequate lubrication of the parts and to be periodically allowed discharge by orifice 44 is nominal and does not appreciably affect engine operation if utilized properly according to the invention.

With regular engine operation the liquid fuel and lubricant is directed against gear 23 and the fuel vaporizes while the lubricant flows on the surface of the gear 3 toward the periphery thereof where it comes in contact with shaft 6 and particularly the teeth 21 thereof. The lubricant on shaft 6 tends to flow between the intermeshing teeth of the gear and shaft to lubricate the same.

The vaporized fuel flows from chamber 25 through the drilled opening 31 and bore 30 in shaft 28 to the registering passages 32 and 33 in the shaft and sprocket 27 for discharge therefrom and any fuel condensation generally occurs immediately upon reaching the atmosphere and is directed toward the chain.

The location of passage 39 from the lowermost point of chamber 8 provides for the draining of the chamber of any excess liquid accumulating therein. This liquid fuel and lubricant is vaporized in chamber 25 unless the accumulation is excessive. While such accumulation in chamber 25 is without disadvantage, such accumulation is not contemplated by the invention as it indicates an unnecessarily excessive proportion of lubricant in the fuel or of liquid fuel and lubricant in the air mixture supplied by the carburetor.

The invention may be employed in various engine powered implements or devices other than chain saws.

Various modes of carrying out the invention are contemplated as within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

1 claim:

1. In an engine-driven implement including an engine employing crankcase precompression of the fuel and air mixture and wherein the lubrication of the engine is pro vided by a liquid lubricant included with the liquid fuel, an enclosed gear transmission vented to the atmosphere, a discharge nozzle directed toward one of the gears of said transmission, a conduit from the crankcase connected to said nozzle, and a spring-held check valve in said conduit preventing flow therein to the crankcase and allowing only limited periodic flow of the fuel and air mixture from the crankcase under the pressure periodically developed therein to be discharged from said nozzle toward said gear to lubricate the same.

2. In an engine driven implement having an exterior mechanism requiring lubrication and including an engine employing crankcase precompression of the fuel and air mixture and wherein the lubrication of the engine is provided by liquid lubricant included with the liquid fuel, an enclosed gear transmission, a discharge nozzle directed toward one of the gears of said transmission, a conduit from the crankcase connected to said nozzle, a springheld check valve in said conduit preventing flow therein to the crankcase and allowing only limited periodic how of the fuel and air mixture from the crankcase under the pressure periodically developed therein to be discharged from said nozzle toward said gear to lubricate the same and others meshing therein, and a passage from said gear transmission openin in said exterior mechanism to lubricate the latter and to vent the transmission.

3. In an engine driven chain saw including a sprocketdriven saw chain requiring lubrication and including an engine employing crankcase precompression of the fuel and air mixture and wherein the lubrication of the engine is provided by liquid lubricant included with the liquid fuel, an enclosed gear transmission, a discharge nozzle directed toward one of the gears of said transmission, a conduit from the crankcase connected to said nozzle, a spring-held check valve in said conduit preventing flow therein to the crankcase and allowing only limited periodic flow of the fuel and air mixture from the crankcase under the pressure periodically developed therein to be discharged from said nozzle toward said gear to lubricate the same and others meshing therein, and a passage from said gear transmission opening onto said sprocket and saw chain to lubricate same and to vent the transmission.

4. In an engine-driven implement including an engine having a crankcase for precompression of the fuel and air mixture and wherein the lubrication 'of the engine is provided by liquid lubricant included with the liquid fuel, a gear case adjacent to said engine crankcase and having a gear chamber, a gear train within said gear chamber comprising at least two gears, a shaft carrying one of said gears and extending exteriorly of the gear case and having means to drive the implement, a discharge nozzle fixed in a wall of said gear case and directed toward one of the gears of said gear train, a conduit from the crankcase connected to said nozzle, a spring-held check valve in said conduit preventing flow therein to the crankcase and allowing only limited periodic fiow of the fuel and air mixture from the crankcase under the pressure periodically developed therein to be discharged from said nozzle and to lubricate said gears, and a passage from said gear case formed partially in said shaft and opening in said means to lubricate the latter and to vent the transmission.

5. In an engine-driven implement including an engine having a crankcase for precompression of the fuel and air mixture and wherein the lubrication of the engine is provided by liquid lubricant included with the liquid fuel, a gear case adjacent to said engine crankcase and having a gear carrying shaft rotatably mounted therein with an end portion extending exteriorly therefrom, means on said portion to drive an implement, a conduit placing said crankcase in fluid communication with said gear case, a spring biased check valve in said conduit whereby lubricant-fuel is periodically forced by maximum crankcase pressure into said gear case and vaporized for lubrication of parts therein, a fluid passageway in said shaft, a fluid passageway in said means, said passageways placing the interior of said gear ease in communication with the atmosphere whereby said case is vented through said passageways and vaporized lubricant-fuel passing therethrough will be condensed upon reaching the atmosphere to lubricate said means.

6. In an engine-driven implement including an engine employing crankcase precompression of the fuel and air mixture and wherein the lubrication of the engine is provided by a liquid lubricant included with the liquid fuel,

an enclosed gear transmission vented to the atmosphere,

a conduit from the bottom of the crankcase and placing the latter in communication with said transmission, and a spring-held check valve in said conduit preventing flow therein to the crankcase and allowing only limited periodic flow of the fuel and air mixture from the crankcase under the maximum pressure periodically developed therein to be discharged from said conduit to lubricate said transmission.

References Cited in the file of this patent UNITED STATES PATENTS 807,731 Dodge Dec. 19, 1905 2,111,242 Harley Mar; 15, 1938 2,605,787 Kiekhaefer Aug. 5, 1952 2,610,657 Kiekhaefer Sept. 16, 1952 FOREIGN PATENTS 396,881 France Feb. 6, 1909 256.067 Great Britain Aug. 5, 1926 $05,648 Belgium Sept. 29, 1951 

